The accurate positioning of an object with respect to a surface provides a necessary element in modern manufacturing processes. For instance, power machinery, whether manually or automatically manipulated, requires the placement of a workpiece in a particular position with respect to the operation performed. As is well known in the art, drill presses, lathes, and other like tools function by locating the workpiece with respect to the tool resulting in the manufacture of high quality artifacts in mass.
The disparity in measuring systems among the world nations (chiefly English and Metric) compounds the problem, since international commerce demands the use of each measuring system in every country. It is apparent that persons unfamiliar with the English system, for example, will be required to convert metric units into English units and vice versa. Such conversion reaches fruition in an ordinary factory or shop, where the worker must perform this task. In the past this process has proved a difficult one.
Likewise, the mere conversion of centimeters to inches creates many other problems in the manufacturing circles. The upshot of such measurement conversions transforms itself into extra time, labor and expense in the production process.
The known construction of positioning machines limits the accuracy to about a one degree turn of the dial. This limitation springs from the friction factors of the known devices and the physical characteristics of the human body. In other words, the average human hand and eye can only perform fine work to a certain extent.